In a typical building, ground potential in the electrical systems of the building needs to be equalized for all networks so that different networks function properly. For example, a power line and cable television (CATV) network require equal ground potentials as they utilize common equipment. For developed countries, the ground installation and setup may be regulated, and thus the networks in a building may not experience issues. On the other hand, other jurisdictions where regulation is less, improper grounding may become an issue when different networks have different ground potentials.
When two networks are connected, for example, when a cable is connected to the CATV set top box, a current will flow from CATV network to a neutral line of the set top box or vice versa if the ground potentials are not equal. In some cases, this current may reach levels that damage the set top box, and may even become hazardous to the user or installer. Therefore, the neutral lines of these networks need to be isolated to prevent current flow.
Currently, there are isolators available to address this problem. However, the available isolators are bulky and expensive. For example, in some isolators, isolation is achieved on a printed circuit board that has two ground metallization: one side of the metalization connected to a female connector side and the other side of the metalization to a male connector. The coupling between two ground metalizations is achieved via a coupling capacitor and electromagnetic interference (EMI) filtering is achieved on the printed circuit board from one side metalization to the other using ferrites. This configuration results in large and bulky isolators.